Hemodynamic and behavioral differences after administration of meloxicam, buprenorphine, or tramadol as analgesics for telemeter implantation in mice.

Cannulation of the common carotid artery for chronic, continuous radiotelemetric recording of aortic hemodynamic properties in mice is a highly invasive recovery surgery. Radiotelemetric recording, by its continuous nature, gives the most accurate measurements of hemodynamic variables in experimental animals, and is widely used in the study of cardiovascular diseases including hypertension. The American Heart Association has recommended data acquisition by radiotelemetric recording but did not provide guidelines regarding postoperative analgesic support. We assessed hemodynamic parameters, locomotor activity, food intake, and weight loss in radiotransmitter-implanted CD1 female mice receiving analgesic support during the first 48 h after surgery. The efficacy of analgesic support from the NSAID meloxicam was compared with that of the widely used opioid agonist buprenorphine and the related compound, tramadol. Meloxicam-treated mice recovered lost body weight more rapidly than did tramadol-or buprenorphine-treated mice. Furthermore, meloxicam-treated mice maintained circadian rhythm after surgery and had tighter regulation of mean arterial pressure than did tramadol- or buprenorphine-treated mice. Meloxicam was also superior with regard to food intake, locomotor activity, and limiting variance in hemodynamic parameters. This study indicates that when compared with buprenorphine and tramadol, meloxicam should be the postoperative analgesic of choice for radiotelemeter implantation in mice.